Files
git-cli/private/git-commands.rkt
T

101 lines
3.7 KiB
Racket

#lang racket/base
(require "git-provider.rkt"
racket/string
racket/list
)
(provide def-git-cmd-proxy
check-git-args
has-git-arg?
std-process-git-result
)
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; goal : Determine whether a Git option occurs in an argument list.
; pre : args is a list and opt is a symbol, string or regular expression.
; post : args has only been inspected.
; result : The match result, or #f when the option is absent.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(define (has-git-arg? args opt)
(let ((cmp (cond ((symbol? opt) (λ (x) (eq? x opt)))
((string? opt) (λ (x) (string=? (format "~a" x) opt)))
((regexp? opt) (λ (x) (regexp-match opt (format "~a" x))))
(else (error "opt must be a string, symbol or regular expression")))))
(letrec ((f (λ (args)
(if (null? args)
#f
(let ((m (cmp (car args))))
(if m
m
(f (cdr args))))))))
(if (list? args)
(f args)
(error 'has-git-arg? "args must be a list of arguments")))))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; goal : Check that mandatory Git options and their arguments are present.
; pre : flags contains (option argument-count error-message) items.
; post : Missing options have raised an exception.
; result : args when every mandatory option is present.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(define (check-git-args cmd args flags)
(for-each
(λ (opt)
(let ((flag (car opt))
(num-args (cadr opt))
(err-msg (caddr opt)))
(letrec ((find (λ (l)
(if (null? l)
#f
(if (eq? (car l) flag)
(if (>= (length (cdr l)) num-args)
#t
#f)
(find (cdr l)))))))
(let ((found (find args)))
(unless found
(error 'git (format "git ~a: ~a" cmd err-msg))))
)
))
flags)
args)
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; goal : Process the standard result of a Git command.
; pre : exit-code and out belong to the completed Git command.
; post : Successful output has been displayed or a Git exception has been raised.
; result : #t when exit-code is zero.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(define (std-process-git-result cmd exit-code result output out info)
(if (= exit-code 0)
(begin
(git-displ (map cadr output))
#t)
(git-error cmd (format "Exitcode <> 0: ~a" exit-code) out)
)
)
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; goal : Define the internal proxy for a Git command.
; pre : pre-code and process-result accept the command proxy arguments.
; post : The proxy invokes Git without standard input and processes its result.
; result : A procedure named f accepting a list of Git arguments.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(define-syntax def-git-cmd-proxy
(syntax-rules ()
((_ f cmd pre-code process-result)
(define (f args*)
(let* ((args (flatten args*))
(info (make-hash))
(nargs (pre-code args info)))
(let-values (((exit-code output) (run-git (cons cmd nargs))))
(let-values (((result out) (git-out cmd output)))
(process-result cmd exit-code result output out info))))))
)
)